N1212C

After the pilot finished the preflight inspection in the hangar, the maintenance technician pulled the airplane out of the hangar and connected the auxiliary power cart to the airplane. Shortly thereafter, the pilot boarded the airplane and proceeded with the normal checklist. The pilot signaled to the maintenance technician to disconnect the power cart. The maintenance technician subsequently signaled that the pilot was clear to start the engines. After departure the pilot noted a problem with the landing gear and after establishing that the tow bar was, most likely, still attached to the nosewheel, he diverted to a nearby airport for a precautionary landing. During the landing, the nose landing gear collapsed and the primary structure in the nose of the airplane was substantially damaged.